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951.
Supplementation of the semen extender with antioxidants did not produce any significant effect on CASA and progressive motilities and sperm motility characteristics, in comparison to the control group (P > 0.05).  相似文献   
952.
Age, growth, spawning period and maturity of the solenette (Buglossidium luteum Risso, 1810) were studied in the central Aegean Sea to provide fisheries managers with essential data for science‐based management. A total of 1220 samples were collected by trawl hauls from July 2004 to June 2007 in ?zmir Bay (Turkey). Sample sizes ranging from 5.3 to 11.6 cm total length were composed of 46% females, 32% males and 22% immature individuals, with a female to male ratio of 1 : 0.7. Age composition stages of the females were from I to IV, and males between I and III. The length–weight relationship was calculated as W = 0.0101L3.008 for all samples. Estimated von Bertalanffy growth parameters were L = 13.30 cm, to = ?0.440 year and k = 0.481 year?1, with a growth performance index of 1.93 (?’). The spawning period began in April and continued until July. Lengths at first maturity of females and males were 8.1 and 7.9 cm total length, respectively. Both sexes matured at the age of 2 years.  相似文献   
953.
This is the first report on the beneficial effect of microalgal and cyanobacterial biomass on anther cultures of maize (Zea mays L.). Investigations were made on the cytokinin- and auxin-like activity and content of terrestrial and fresh-water living microalgal and cyanobacterial strains. The influence of media supplemented with biomass from four selected strains on the anther induction, the frequency of microspore-derived embryo-like structures, and regeneration capacity in anther cultures of maize was also studied. The addition of cyanobacterial and microalgal biomass to the induction and regeneration media in concentrations of 1 or 2 g/L improved the androgenic response, and was able to reduce the quantity of the synthetic auxin 2,4-dichlorophenoxy-acetic acid (2,4-D) required, or replace it completely.  相似文献   
954.
955.
We aim to ascertain the possible involvement of functional IL10 and TNF-α promoter polymorphisms on the susceptibility to Behçet’s syndrome (BS), to examine whether IL10 and TNF-α genotypes might work synergistically influencing susceptibility to BS. IL10 ?1082G/A, ?819C/T and ?592C/A and TNF ?308G/A polymorphisms were analyzed in 102 Turkish patients with BS and 102 healthy subjects by using amplification refractory mutation system-polymerase chain reaction (ARMS-PCR). We have found no significant associations between IL10 ?1082G/A, ?819C/T, ?592C/A, TNF-α ?308G/A polymorphisms and BS. Also, no significant correlation was found between IL10 GCC, ACC, ATA haplotypes, GCC+/GCC+, GCC+/GCC?, GCC?/GCC? genotypes. There was no significant association between combined TNF-α/IL10 genotypes and BS. Our study indicates that functional TNF-α, IL10 genotypes or combined TNF-α, IL10 genotypes do not play a role in BS susceptibility in Turkish BS patients.  相似文献   
956.
Pituitary adenylate cyclase activating polypeptide (PACAP)-like molecules have been shown to be present in cocoon albumin and in Eisenia fetida embryos at an early developmental stage (E1) by immunocytochemistry and radioimmunoassay. Here, we focus on detecting the stage at which PAC1 receptor (PAC1R)-like immunoreactivity first appears in germinal layers and structures, e.g., various parts of the central nervous system (CNS), in developing earthworm embryos. PAC1R-like immunoreactivity was revealed by Western blot and Far Western blot as early as the E2 developmental stage, occurring in the ectoderm and later in specific neurons of the developing CNS. Labeled CNS neurons were first seen in the supraesophageal ganglion (brain) and subsequently in the subesophageal and ventral nerve cord ganglia. Ultrastructurally, PAC1Rs were located mainly on plasma membranes and intracellular membranes, especially on cisternae of the endoplasmic reticulum. Therefore, PACAP-like compounds probably influence the differentiation of germinal layers (at least the ectoderm) and of some neurons and might act as signaling molecules during earthworm embryonic development.  相似文献   
957.
Vinblastine is a widely used anticancer drug with undesired side effects. Its conjugation with carrier molecules could be an efficient strategy to reduce these side effects. Besides this, the conjugate could exhibit increased efficiency against resistant cells, e.g., due to the altered internalization pathway. Oligoarginines, as cell-penetrating peptides, can transport covalently attached compounds into different kinds of cells and enhance the efficiency of those compounds. We report here the coupling of vinblastine through its carboxyl group at position 16 with the N-terminal amino function of L-Trp methyl ester. After hydrolysis of the ester group, 17-desacetylvinblastineTrp was conjugated to the N-terminal amino group of oligoarginine via the C-terminal carboxyl group of the Trp moiety in solution. The antitumor effect of conjugates was studied on sensitive and resistant human leukemia (HL-60) cells in vitro. Our data suggest that all conjugates investigated possess an antiproliferative effect against the studied cells. However, the effect was dependent on the number of Arg residues in the conjugates: Arg? > Arg? ? Arg?. The conjugate with Arg? exhibited similar efficicacy as compared with free 17-desacetylvinblastineTrp. The in vitro studies also showed that the tubulin binding ability of vinblastine was essentially preserved even in the octaarginine conjugate. We also observed that two isomers were formed during conjugation. These isomers showed different levels of activity against tubulin polymerization in vitro and in vivo. The 17-desacetylvinblastineTrp-Arg?-1 isomer conjugate possessed high selectivity against the mitotic spindles. HRMS and NMR data suggest that 17-desacetylvinblastineTrp-Arg?-1 and 17-desacetylvinblastineTrp-Arg?-2 are epimers at the tryptophan α carbon atom.  相似文献   
958.
Understanding how species responded to past climate change can provide information about how they may respond to the current global warming. Here we show how a European reptile species responded to the last natural global warming event at the Pleistocene-Holocene transition that led to the Holocene climatic optimum approximately 5000-8000 years ago. The Aesculapian snake, Zamenis longissimus, is a thermophilous species whose present-day distribution in the southern half of Europe is a remnant of much wider range during the Holocene climatic optimum when populations occurred as far north as Denmark. These northern populations went extinct as the climate cooled, and presently the species is extinct from all central Europe, except few relic populations in locally suitable microhabitats in Germany and the Czech Republic. Our phylogenetic and demographic analyses identified two major clades that expanded from their respective western and eastern refugia after the last glacial maximum (18,000-23,000 years ago) and contributed approximately equally to the present range. Snakes from the relic northern populations carried the Eastern clade, showing that it was primarily the snakes from the eastern, probably Balkan, refugium that occupied the central and northern Europe during the Holocene climatic optimum. Two small, deep-branching clades were identified in near the Black Sea and in Greece. These clades provide evidence for two additional refugia, which did not successfully contribute to the colonization of Europe. If, as our results suggest, some populations responded to the mid-Holocene global warming by shifting their ranges further north than other populations of the same species, knowing what populations were able to expand in different species may provide information about what populations will be important for the species' ability to cope with the current global warming.  相似文献   
959.
BiP is the mammalian endoplasmic reticulum (ER) Hsp70 orthologue that plays a major role in all functions of this organelle including the seemingly opposing functions of aiding the maturation of unfolded nascent proteins and identifying and targeting chronically unfolded proteins for degradation. The recent identification of mammalian BiP co-factors combined with delineation of the ER degradation machinery and data suggesting that the ER is subdivided into unique regions helps explain how these different functions can occur in the same organelle and raises some unresolved issues.  相似文献   
960.
We designed a randomized, rater blind study to assess the efficacy of EEG Biofeedback (Neurofeedback-NFB) in patients with fibromyalgia syndrome (FMS). Eighteen patients received twenty sessions of NFB-sensory motor rhythm (SMR) treatment (NFB group) during 4 weeks, and eighteen patients were given 10 mg per day escitalopram treatment (control group) for 8 weeks. Visual Analog Scales for pain and fatigue, Hamilton and Beck Depression and Anxiety Inventory Scales, Fibromyalgia Impact Questionnaire and Short Form 36 were used as outcome measures which were applied at baseline and 2nd, 4th, 8th, 16th, 24th weeks. Mean amplitudes of EEG rhythms (delta, theta, alpha, SMR, beta1 and beta2) and theta/SMR ratio were also measured in NFB group. All post-treatment measurements showed significant improvements in both of the groups (for all parameters p < 0.05). NFB group displayed greater benefits than controls (for all parameters p < 0.05). Therapeutic efficacy of NFB was found to begin at 2nd week and reached to a maximum effect at 4th week. On the other hand, the improvements in SSRI treatment were also detected to begin at 2nd week but reached to a maximum effect at 8th week. No statistically significant changes were noted regarding mean amplitudes of EEG rhythms (p > 0.05 for all). However, theta/SMR ratio showed a significant decrease at 4th week compared to baseline in the NFB group (p < 0.05). These data support the efficacy of NFB as a treatment for pain, psychological symptoms and impaired quality of life associated with fibromyalgia.  相似文献   
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